mobile phones in cryptogenic stroke patients bringing single lead ecgs to detect atrial fibrillation

Conditions: Atrial Fibrillation; Ischemic Stroke; Transient Ischemic Attack

Summary: the main objective of this study is to compare the incidence of detected atrial fibrillation (af) in cryptogenic stroke patients by a single lead ecg device with the incidence of detected af by a 7-day holter ecg.

rationale: a standard work-up of stroke patients to identify a cause of stroke consists of computed tomography (ct), ct angiography of head and neck arteries, transthoracic echocardiography, 12-lead 10-seconds electrocardiogram (ecg), blood tests and 24-hour ecg monitoring. a stroke is called "cryptogenic" if no cause can be determined after standard work-up. current detection of atrial fibrillation (af) after stroke is 2.0%. recent studies revealed that prolonged monitoring yields higher percentages of detected af (12.0%). devices used in these trials suffer from drawbacks. the investigators' hypothesis is that a new, smartphone compatible device, producing a single lead ecg (single lead ecg device), can be used for prolonged ecg monitoring in cryptogenic stroke patients. objective: the main objective of this study is to compare the incidence of detected af in cryptogenic stroke patients by a single lead ecg device with the incidence of detected af by a 7-day holter ecg. study design: a multicenter randomized trial. study population: cryptogenic stroke patients admitted to a hospital participating in the study. the calculated sample size is 200 (100 per arm). intervention: after inclusion, patients will be randomized to either a single lead ecg device or a 7-day holter monitor. main study parameters/endpoints: the main endpoint will be the percentage of detected atrial fibrillation in both the single lead ecg device group and the 7-day holter group after one year. nature and extent of the burden and risks associated with participation, benefit and group relatedness: both devices are battery powered and electrically safe. patients face a 2-3% risk that af is detected false-positively; this might lead to incorrect oral anticoagulation (oac) prescription. however, a potential benefit of the investigators' study is that if af is detected and treated with oac, this significantly reduces the chance of recurrent stroke.

Eligibility criteria:
inclusion criteria: * patients must have had an episode of symptomatic transient ischemic attack (tia) or episode of ischemic stroke. * ischemic stroke is defined as an episode of transient or neurological dysfunction caused by focal brain or retinal ischemia with recent infarction on imaging * a tia is defined as transient episode of neurologic dysfunction typically lasting less than one hour caused by focal brain or retinal ischemia without recent infarction on imaging. exclusion criteria: * known etiology of tia or ischemic stroke * tia or stroke caused by spinal ischemia * tia only presenting with non-localising symptoms * uncertainty about the diagnosis of tia because of unclear clinical symptoms * myocardial infarction \<6 months before stroke * coronary artery bypass grafting \<6 months before stroke * severe valvular heart disease * documented history of atrial fibrillation or atrial flutter * permanent indication for oral anticoagulation at enrolment * patient has permanent oac contraindication * patient is included in another randomized trial * left ventricular aneurysm on echocardiography * thrombus on echocardiographyrenal dysfunction (creatinine clearance \<30 ml/min/1.73m2) * patient has life expectancy of \<1 year * patient is not willing to sign the informed consent form * patient is \<18 years of age * patient is considered an incapacitated adult * patient is not in possession of a smartphone with android operating system (os) or ios.